The example acting as the guiding thread of the present description is the steering column of a vehicle. The existence of out-of-round, resulting directly from the manufacture of the steering column, distorts the angular measurement by sometimes accelerating and sometimes retarding the rotation. The curve of the measured angle as a function of the true angle is not, therefore, linear. The rotating system, in particular formed of the steering column and the disc supporting the means for angular coding not being a homokinetic system, it is necessary to measure the out-of-round to perform an angle correction in order to linearize the output signal.
Until now, the means to remedy this problem was principally mechanically formed, i.e. extremely precise mechanical solutions were implemented, with altogether unfavourable economic and therefore industrial consequences.